Boletales – Boletaceae s.l. (26 October 2020, © R. E. Halling)

NOTE: 104 genera listed here are conceived in a broad, classical sense (generally the fleshy stipitate mushrooms with pores) including sequestrate morphologies. Phylogenetic inferences from DNA sequences suggest alignment in suborders: Boletineae, Suillineae, Sclerodermatineae, or in the Paxillaceae. Not all genera are well known, equally circumscribed or robustly inferred phylogenetically. Mycorrhizal associations may be confirmed, but many are presumed or suspected. Recent phylogenetic analyses based on DNA sequences infer some true gasteroid (truffle-like, sequestrate) taxa (aside from those in Sclerodermatineae, Suillineae) belong here. Some of the diagnoses are from protologues. Year of publication follows authority (-ies).

Afroboletus Pegler & Young (1981) Pileus dry, coarsely fibrillose to squamose, black, often with appendiculate veil remnants, microscopically a trichodermium. Context white, staining red then black. Hymenophore adnexed, white then black, staining red then black. Peronate veil present. Stipe dry, squamose, sometimes annulate, white to gray to black. Spores black, short ellipsoid, longitudinally ridged or winged, sometimes with intercostal veins; a basal thickened rim around sterigmal appendage, lacking a plage. Hymenial cystidia present. Clamp connections absent. Apparently restricted to the African tropics. One sequestrate species known. Ectomycorrhizae presumed with caesalpinoid legumes.

Afrocastellanoa M.E. Smith & Orihara (2017) From the protologue: Basidiomata sequestrate, gasteroid, firm, rubbery, with one or a few rhizomorphs at the base. Similar to Octaviania in the morphology of the basidiome and basidiospores, but different from Octaviania in the multilayered peridium and in basidia that are irregularly distributed within the solid gleba, resulting in the absence of a distinct hymenium and subhymenium. Phylogenetically related to the epigeous bolete genus Porphyrellus, but distantly related to the genus Octaviania s.s. One sequestrate species known, A. ivoryana. Ectomycorrhizal with Anthonotha (Fabaceae), Uapaca (Uapacaceae), and probably with other legumes in sub-Saharan Africa.

Alessioporus Gelardi, Vizzini, & Simonini (2014) Originally described as a monotypic genus for Xerocomus ichnusanus, a thermo-xerophilic taxon in Mediterranean Europe. The taxon, based on a summary of features in the protologue indicate it is a medium- small species, exhibiting an ochraceous-brown to dark olivaceous brown fibrillose pileus, sometimes with copper red hues and a wavy margin at least in young specimens, a yellow to olive colored hymenophore and a stout, deeply rooting stipe covered with a rough and darker net that is rarely absent, bright yellow at the apex, dark red-brown to blackish brown elsewhere and with a whitish gray basal mycelium. The context is whitish in the pileus, yellowish in the stipe with reddish shades, purplish red to brownish black at the base, turns uniformly blue on exposure, as do the external surfaces after injury or bruising. The most important morphological character is the narrow, granular ring-like zone in the middle or lower half of the stipe, formed by the remnants of the connection between the pileus margin and the stipe cortex during the primordial stage. A 3-gene analysis infers a relationship with Pulchroboletus near Hemileccinum in the Xerocomoideae. A second species, A. rubriflavus, was inferred by Frank et al from E USA. Ectomycorrhizae presumed with Fagaceae, possibly Pinaceae (USA).

Alpova Dodge (1931) Sequestrate, globose to irregular in shape. Peridium well developed, variable in thickness, usually dry, whitish but usually discoloring with age and handling. Gleba sticky and gelatinous, with gel-filled chambers, not forming a true hymenium, separated by pale colored veins, pale colored at first, but darkening with age. Spores hyaline, ellipsoid to oblong, smooth, inamyloid, strongly cyanophilic when young. Clamp connections usually present. At present confined to Northern Hemisphere. Ectomycorrhizae with Betulaceae, possibly Pinaceae or Fagaceae.

Aureoboletus Pouzar (1957) Pileus viscid to dry, rugulose to even. Context white, unchanging. Hymenophore tubulose, bright yellow at first, greenish yellow with age in some, not oxidizing. Stipe central, glabrous, sometimes superficially pruinose or lacerate ridged, viscid or dry, rarely with a veil. Spores olive brown in deposit, smooth or rarely with conspicuous longitudinal ridges, fusoid to ovoid, inamyloid. Clamp connections absent. Mostly north temperate to pantropical. Ectomycorrhizae with Pinaceae, Fagaceae.

Australopilus Halling & Fechner (2012) Basidiomata epigeous. Pileus gray to dark gray, sometimes pink to deep pink pigments present. Context white, unchanging. Hymenophore tubulose, white then vinaceous pink. Stipe white above, chrome yellow at base, beset with either fine isolated pink scabers or these often arranged in a well-defined or ill-defined raised reticulum, sometimes scattered on low longitudinal ridges. Spores pinkish to reddish brown in deposit, smooth, fusoid. Pileipellis a trichodermium. Hymenial cystidia present. Pseudocystidia absent. Clamp connections absent. Australia. Ectomycorrhizae with Myrtaceae, Casuarinaceae.

Austroboletus (Corner) C.B. Wolfe (1980) Pileus viscid or dry, tomentose to subtomentose, microscopically a trichodermium or ixotrichodermium, sometimes with appendiculate remnants at margin. Context white or yellow, unchanging. Hymenophore tubulose, adnexed, white at first, pinkish flesh colored to brownish pink with maturity (rarely yellow), sometimes staining light brownish to pinkish brown. Stipe central, pruinose to alveolate-reticulate, dry or sometimes glutinous-viscid, not staining or developing stains in situ from aging; basal mycelium white. Spores vinaceous pink in deposit, obscurely pitted to pitted to sinuous pitted, sometimes equatorially verrucose, amygdaliform to elongate-fusoid, inamyloid or dextrinoid. Hymenial cystidia usually present. Clamp connections absent. KOH & NH4OH reactions negative. Mostly E Asia, Australasia; some temperate, montane and lowland tropics of New World. Ectomycorrhizae with Pinaceae, Fagaceae, Myrtaceae, Dipterocarpaceae, Casuarinaceae.

Baorangia G. Wu & Zhu L. Yang (2015) Basidiomata stipitate-pileate. Pileus hemispherical, convex or applanate, subtomentose, dry, usually incurved at the margin when young. Context pale yellow to yellow, slowly staining pale blue when cut. Hymenophore relatively thin (1/3–1/5 of pileal context midway from disc to margin), usually decurrent, yellow, immediately staining light blue to greenish blue when injured; pores angular, or sometimes nearly round; tubes short. Stipe smooth or occasionally with reticulations at the upper part; context pale yellow to yellow, basal mycelia white to pale yellow. Pileipellis a trichodermium to an interwoven trichodermium. Hymenial cystidia present. Basidiospores smooth, subfusiform to elongated subfusiform, light yellow to brownish-yellowish. Clamp connections absent. Eastern Asia, eastern North America. Ectomycorrhizae presumed with Pinaceae, Fagaceae.

Binderoboletus T.W. Henkel & M.E. Smith (2016) Basidiomata epigeous. Pileus olive-yellow to olive-brown, matted fibrillose, trama light yellow, unchanging. Hymenophore tubulose, adnate, light yellow, browning with pressure, pores subisodiametric. Stipe subequal, concolorous and striate, yellow and reticulate at apex, base yellow tomentose, trama bright yellow. Basidiospores olivaceous brown in deposit, smooth, dextrinoid in Melzer’s reagent. Pleurocystidia present, dextrinoid in Melzer’s reagent. Cheilocystidia present. Hymenophoral trama parallel to slightly divergent (phylloporoid). Pileipellis an entangled cutis, terminal cells cylindrical. Clamp connections absent. Reminiscent of Retiboletus macro- and microscopically. According to the describing authors, it is related to Retiboletus in the Leccinoideae of Wu et al (2014), but the ITS sequences are highly unique. Monotypic species from Guyana. Ectomycorrhizae with Dicymbe, Aldina (caesalpinoid legumes)

Boletellus Murrill (1909) Pileus typically dry, rarely subviscid, scaly or tomentose, microscopically a trichodermium, sometimes with appendiculate remnants at margin. Context white or yellow, often changing to blue. Hymenophore tubulose, adnexed, white at first, soon yellow, often staining blue. Stipe central, usually pruinose, rarely with an apical reticulum, dry, rarely subviscid and annulate, sometimes staining blue; basal mycelium white, very rarely yellow or olive colored. Spores olive brown in deposit, longitudinally ridged/winged or slightly veined, cleft, dimpled or entire at apex, inamyloid or rarely dextrinoid. Hymenial cystidia usually present. Clamp connections usually absent, rarely present (one sp., B. fibuliger). KOH & NH4OH reactions negative (more species need testing). N Hemisphere, temperate South America, Mesoamerica, Andean and Amazonian Colombia, one sp. in Venezuela (B. fibuliger), four spp. in Guyana, Amazonian and NE Brazil, central Africa, Australia, E Asia, SE Asia. Ectomycorrhizae with Pinaceae, Fagaceae, Myrtaceae, Dipterocarpaceae, Casuarinaceae, caesalpinoid legumes (e.g., Dicymbe), possibly Euphorbiaceae.

Boletinellus Murrill (1909) Pileus dry, usually glabrous but sometimes finely tomentose to matted tomentose, soft textured, microscopically a repent entangled interwoven layer. Context pale yellowish, rarely cyanescent. Hymenophore tubulose, quite decurrent and with a radial boletinoid orientation, occasionally sublamellate, dull yellow, slowly cyanescent then brownish. Stipe lateral or eccentric, very rarely nearly central, dry, mostly glabrous. Sclerotia present. Spores olive brown in deposit, ovoid to nearly globose, smooth. Hymenial cystidia inconspicuous, often absent on the pores. Clamp connections present. Not ectomycorrhizal. The type of the genus, B. merulioides is widespread in eastern North America where it is associated with Fraxinus, but is not mycorrhizal. Rather it is associated with a parasitic aphid restricted to Fraxinus roots. There is a well-documented report of its occurrence in Kyushu, Japan. Also, quite possibly in Queensland, Australia.

Boletochaete Singer (1944) Pileus velutinous, bay-colored. Tubes gray. Stipe brownish, nearly smooth. Flesh white, unchanging. Spore deposit cinnamon brown, Spores ovoid, smooth, inamyloid. Pileipellis a palisade with conical terminal elements. Seta-like or pseudocystidia-like hymenial cystidia present. Clamp connections absent. Not well studied. Perhaps 3(-4) species known from SE Asia. Ectomycorrhizae not determined with certainty – probably Fagaceae and/or Dipterocarpaceae.

Boletus L. (1753) Pileus dry to subviscid, glabrous to tomentose to fibrillose, microscopically a trichodermium or ixotrichodermium. Context white, not changing. Hymenophore adnexed to adnate, white to yellow to greenish yellow, not changing with pores occluded ("stuffed") when young, concolorous or sometimes red to brownish red in aged specimens. Stipe dry, glabrous to subpruinose to reticulate or sometimes nearly alveolate, with basal mycelium white. Spore deposit olive brown. Spores smooth, fusoid. Hymenial cystidia present. Clamp connections absent. Mostly temperate northern hemisphere, a few in paleo- neotropics. In southern hemisphere, one sequestrate in New Zealand (B. semigastroideus), one in northern Queensland (B. austroedulis). Boletus edulis sometimes appearing with exotic Pinaceae planted outside native range. Ectomycorrhizae with Pinaceae, Fagaceae, Betulaceae, Dipterocarpaceae (?), Myrtaceae, Casuarinaceae, caesalpinoid legumes(?). Possibly other families less commonly. Note: This genus remains after all others have been separated based on molecular phylogenetic analyses or other idiosyncratic features. Monophyly inferred from molecular phylogenetics suggests restriction to the ‘porcini’ clade (i.e., Boletus edulis etc.). Also included here are some sequestrate species (B. subalpinus, B. semigastroideus).

Borofutus Hosen & Zhu L. Yang (2012) Pileus squamulose, microscopically a trichodermium. Context usually unchanging, but slowly pale reddish to pale reddish purple. Hymenophore subdecurrent, with broad pores, pallid to cream colored at first, then yellowish to golden brown, staining brownish red. Stipe central, glabrous and ribbed above, squamulose below, with whitish basal mycelium. Spores purple to purplish red to purplish violet in KOH with light microscope optics, boletoid to subamygdaliform, with shallow pits (regular to irregular). Hymenial cystidia present, lageniform, thick-walled. Clamp connections absent. Tropical Asia (Bangladesh, Thailand). Apparently phylogenetically allied to the sequestrate Rhodactina, Spongiforma, and epigeous Ionosporus. Ectomycorrhizae with Dipterocarpaceae (Shorea).

Bothia Halling, Baroni & Binder (2007) Pileus dry, coarsely tomentose to subtomentose to aggregated fibrillose or appressed fibrillose, microscopically a trichodermium. Context soft textured, whitish, not cyanescent. Hymenophore decurrent, shallow, conspicuously boletinoid, often with compound pores, pale brown, staining darker brown. Stipe dry, central or eccentric, pale brown, staining darker brown, frequently reticulate at least at the apex, with white basal mycelium. Spores yellow brown in deposit, ellipsoid to long ovoid, smooth, inamyloid. Hymenial cystidia present and conspicuous. Clamp connections absent. Eastern North America, China. Ectomycorrhizae with Fagaceae (Quercus).

Buchwaldoboletus Pilát (1969) Pileus dry, unpolished, sometimes subtomentose, microscopically a collapsed trichoderm or cutis. Context pale colored, usually unchanging but sometimes with a cyanescence just above hymenophore. Hymenophore adnexed, adnate to decurrent, yellow to olivaceous, rarely bruising brownish or cyanescent. Stipe central to sometimes eccentric, dry, smooth and lacking ornamentation. Spores ellipsoid to short-subfusoid, smooth, inamyloid. Hymenial cystidia present, variously shaped. Clamp connections absent. North temperate zone, some tropical, and vouchered reports from southern hemisphere. Mycoparasitic with one species closely associated with Phaeolus schweinitzii and rotting Pinaceae wood.

Butyriboletus D. Arora & J.L. Frank (2014) Basidiomata epigeous and stipitate. Pileus mostly brown to reddish. Hymenophore with tube layer yellow, often turning blue when bruised. Stipe yellow or reddish tinged and reticulate over the upper portion. Context of pileus pale yellow, turning blue erratically if at all when cut; context of stipe often vinaceous-tinged at the base. Spores fusoid, smooth, brown (olive brown in mass); pileipellis a trichodermium. Clamp connections absent. North temperate zone and possibly montane neotropics. Ectomycorrhizae with Pinaceae and Fagaceae.

Cacaoporus Raspé & Vadthanarat (2019)

From the protologue: Basidiomata similar to Sutorius but differs in that this genus is a chocolate brown to blackish-brown overall, without any violet tinges; the hymenophore is not separable from the pileus context; basal mycelium of the stipe is white and rubescent; context is rubescent. Spores in deposit dark brown, smooth, amygdaliform to ovoid, sometimes with acute apex. Phylogenetic inference based on four genes (atp6, rpb2, tef1, cox3) places the genus near Cupreoboletus and Cyanoboletus in the Pulveroboletus group. Two species known from Thailand and so far known from mid- to high elevation forests. Ectomycorrhizae presumed with Dipterocarpaceae, Fagaceae.

Caloboletus Vizzini (2014) Basidiomata stipitate-pileate with tubular hymenophore. Pileus usually pale, whitish to smoke-grey, clay-buff, often with ochraceous/olivaceous tinges, rarely with red tinges, gradually darkening, not turning blue when bruised. Context whitish to pale lemon-yellow, sometimes with red tinges at stipe base, gradually changing to blue when cut. Tubes and pores at first lemon-yellow to sulphur-yellow (but pores are orange to red in Caloboletus firmus), then olivaceous, blue when injured. Hymenophoral trama bilateral-divergent of the Boletus-subtype. Stipe central, pale yellow to yellow, with or without red tinges, usually reticulated, reticulum sometimes reduced or even absent. Taste bitter (presence of cyclocalopins), fading with age. Spores boletoid, smooth. Clamp connections absent. Northern Hemisphere. Ectomycorrhizae with Pinaceae, Fagaceae.

Carolinigaster M.E. Smith & S. Cruz (2018) From the protologue: Basidiomata hypogeous to partially emergent, sequestrate, globose to subglobose. Peridium not changing color when handled. Gleba loculate. Stipe or columella lacking. Basidiospores statismosporic, globose to subglobose, ornamented with short irregular warts at maturity, pink in water and inamyloid but strongly dextrinoid, bleaching to almost hyaline in KOH. Clamp connections and hymenial cystidia absent. The type species, C. bonitoi, described from North Carolina, USA, is inferred to belong in the subfamily Austroboletoideae, sister to Mucilopilus (sine type) without support, based on ITS, LSU and tef1 sequences. Ectomycorrhizae presumed with Fagaceae and Pinaceae.

Castellanea T.W. Henkel & M.E. Smith (2015) Basidiomata sequestrate, with a short stipe, orange brown peridium, brown, loculate gleba, with a short columella arising from a sterile pad, with smooth subfusoid basidiospores that are frequently dextrinoid, lacking clamp connections and hymenial cystidia. Molecular inference places the taxon within a clade containing several species of Tylopilus without bootstrap support. Monotypic species in Guyana. Ectomycorrhizae with Dipterocarpaceae (Pakaraimaea), Caesalpinoid legumes (Dicymbe).

Chalciporus Bataille (1908) (=Rubinoboletus) Pileus dry or subviscid, glabrous, microscopically a trichodermium. Context pale yellow or white or rarely pale pinkish, staining blue in some. Hymenophore adnate to subdecurrent, dull red, cinnamon brown, carmine to salmon pink, not staining or rarely staining blue. Stipe dry, pruinose to glabrous, with bright yellow basal mycelium. Spores brown in deposit, fusoid or short ellipsoid, smooth. Hymenial cystidia present. Clamp connections absent. North Temperate and Pantropical. Some dubious reports from southern Hemisphere; possibly native in New Zealand, but also exotic. Chalciporus piperatus and C. piperatoides are exotic invasive in Australia brought in on roots of Pinus. True Australian natives found in NSW in 2017 (Prichard, unpublished). Putatively mycoparasitic on Amanita muscaria (at least C. piperatus), but possibly ectomycorrhizal with Pinaceae, Fagaceae and Myrtaceae for some taxa.

Chamonixia Rolland (1899) Basidiomata sequestrate, globose to subglobose, dry, white at first, soon staining blue, with basal rhizomorphs. Gleba whitish when young, brown when mature, with peridial trama and columella soon cyanescent. Spores brown, with 8-10 longitudinal ridges. Clamp connections absent. Europe and North America. Phylogenetic placement in a leccinoid clade and basal to a western Pacific genus, Rossbeevera. Ectomycorrhizae with Pinaceae.

Chiua Y.C. Li & Zhu L. Yang (2016) From the protologue: Basidiomata stipitate-pileate with tubular hymenophore. Pileus hemispherical to subhemispherical or convex; surface subtomentose, dry, slightly extended at the margin when young; context yellow to bright yellow, unchanging in color when injured. Hymenophore depressed around apex of stipe; hymenophoral surface white when young, and becomes pinkish or pink to purplish when mature; pores angular or roundish; tubes concolorous with hymenophoral surface, unchanging in color when injured. Stipe central, yellow to lemon yellow at upper part, bright yellow to chrome yellow at the base; basal mycelium chrome yellow. Basidiospores smooth, subfusiform. Pleuro- and cheilocystidia subfusiform to ventricose or clavate. Pileipellis subcutis or trichodermium composed of filamentous interwoven hyphae, or hypoepithelium composed of filamentous hyphae and concatenated subglobose cells. Clamp connections absent. Gene inference indicates the genus is distinct in the Zangioideae. Four species known from southern China, Thailand. Ectomycorrhizae presumed with Fagaceae, Pinaceae.

Chlorogaster Lassøe & Jalink (2004) From the protologue: Gasterocarp epigeous, slenderly pyriform to broadly clavate, pseudostipitate, entirely covered with dark green to blackish conspicuous conical warts. Peristome present. Exoperidium consisting of irregular (rounded) angular, almost isodiametric to rectangular elements, clearly delimited from the hyphal endoperidium. True capillitium lacking, paracapillitium present. Gleba dark grey, non-gelatinous when submature, with white veins and very firm, then more fluffy and dull olive with age. Spores globose, dark brown, with very high, crested ornament, up to 30 µm in diameter including ornamentation. Clamp connections absent. Hypothesized to belong to the Sclerodermataceae. One species, C. dipterocarpi, from Sabah, Malaysia. Ectomycorrhizae presumed with Dipterocarpaceae.

Corneroboletus N.K. Zeng & Zhu L. Yang (2012) Pileus convex becoming plane; surface mucilaginous, covered with conical to subconical to irregularly shaped squamules, microscopically an ixohyphoepithelium. Hymenophore yellow to olivaceous yellow, turning reddish brown slowly when injured. Stipe central, cylindrical; surface covered with conical to subconical to irregularly shaped squamules, but apical part nearly smooth. Spores subfusiform to ellipsoid, smooth under light microscopy but irregularly warted to irregularly bacillate with SEM. Hymenial cystidia present. Clamp connections absent. One species, C. indecorus, known from Singapore, Malaysia, tropical China. Ectomycorrhizae likely with Fagaceae.

Costatisporus T.W. Henkel & M.E. Smith (2015) From the protologue: Basidiomata hypogeous to partially emergent, sequestrate. Peridium greyish yellow, staining dark blue, glabrous to subtomentose, thin. Gleba brown, unchanging, loculate, sterile veins absent. Basidiospores statismosporic, subglobose to oblong, light brown, inamyloid, with costate ornamentation of longitudinal ridges pole to pole; these entire or discontinuous; pedicel infrequent. Basidia clavate. Cystidia and clamp connections absent. A relationship within Boletaceae is inferred from molecular analysis which infers Costatisporus is a sister taxon to Sutorius. Monotypic with one species, C. cyanescens, from Guyana. Ectomycorrhizae with Caesalpinoid legumes (Dicymbe, Aldina).

Crocinoboletus N.K. Zeng, Zhu L. Yang & G. Wu (2104) Basidiomata epigeous. Pileus convex to applanate, surface yellowish orange, bright orange to reddish orange, covered with minute, reddish brown squamules, turning bluish olivaceous quickly, then blackening when bruised. Context vivid golden yellow, turning bluish olivaceous quickly when bruised. Hymenophore poroid, adnate or slightly depressed around apex of stipe; tubes orange, turning bluish olivaceous quickly, then blackening when bruised. Stipe centrally attached, subcylindric, concolorous with the pileus, sometimes with reddish orange squamules, turning bluish olivaceous quickly, then blackening when bruised. Spores subfusiform to ellipsoid, smooth. Pleuro- and cheilocystidia present. Pileipellis an interwoven trichoderm at the middle part of the pileus but a cutis at the margin of the pileus. Clamp connections absent. Polyene pigments boletocrocins present. Two species known: C. rufoaureus, C. laetissimus. Eastern Asia, Australia. Ectomycorrhizae presumed with Pinaceae, Fagaceae, Myrtaceae, Casuarinaceae(?).

Cupreoboletus Simonini, Gelardi & Vizzini (2015) A former member of Boletus sect. Luridi, with reticulate stipe, the taxon produces peculiar protruding crystals on the hymenophore along with pseudocystidia. Odor is described as intense and sweet, recalling propolis, cinnamon or poplar flower buds. Four-gene molecular phylogenetics infer placement as a sister genus to Cyanoboletus on a well-supported polytomic clade. Monospecific, C. poikilochromus, in thermophilic southern Europe. Ectomycorrhizae assumed with Quercus.

Cyanoboletus Gelardi, Vizzini & Simonini (2014) Basidiomata pileate-stipitate with tubular-poroid hymenophore, epigeal, small to medium- small, evelate. Pileus tomentose to glabrous, dry to slightly tacky. Context yellowish, often reddish- tinged at the base of stipe, instantly discoloring dark indigo blue to blue-blackish when handled or injured, inamyloid. Taste mild. Tubes adnate to depressed around the stipe, yellow to olive-green. Stipe surface smooth to pruinose, transversely streaked-scissurate or occasionally reticulate. Spores olive-brown in deposit, smooth, ellipsoidal to ellipsoidal-fusoid. Hymenial cystidia present. Pileipellis a trichodermium. Hymenophoral trama bilateral-divergent of the 'Boletus-type'. Lateral stipe stratum of the 'boletoid type'. Clamp connections absent. Northern Hemisphere. Ectomycorrhizae with Pinaceae, Fagaceae.

Durianella Desjardin, A.W. Wilson, Manfr. Binder (2008) Basidiomata sequestrate, globose to somewhat flattened, dry, covered with yellow brown, short, conical warts. Gleba with dark, gelatinized locules, deep indigo blue to black with exposure, with white sterile trama, also deep blue-black on exposure. Spores globose to subglobose, with straight to curved conical spines. Clamp connections absent. One species, D. echinulata, known from Malaysia and Borneo. Molecular phylogenetic inference, while suggesting placement in the Boletineae (Zangioideae?), is equivocal in relationships to known taxa. Ectomycorrhizae likely with Shorea.

Erythrophylloporus Ming Zhang & T.H. Li (2018) From the protologue: Basidiomata epigeous, small to medium‐sized, stipitate‐pileate with lamellate hymenophore. Pileus convex to applanate, dry, pruinose or velutinous, subtomentose to faintly squamulose or subfloccose towards the center, orange, deep orange, yellowish red to reddish orange. Context vivid yellow to orange yellow, gradually changing dark violet, blackish blue to dark blue when exposed. Hymenophore decurrent, lamellate, yellowish orange, orange, deep orange, reddish orange to orange red changing grayish blue, grayish turquoise to grayish green when bruised. Stipe central, solid, subcylindrical or clavate, orange, yellow, reddish orange to yellowish red, with orange, reddish orange to orange red pruinose scales on surface, basal mycelium vivid yellow. Basidiospores broadly ellipsoid, ellipsoid to nearly ovoid, smooth, thin‐walled. Pleuro‐ and cheilocystidia present, usually containing yellowish brown pigment, slowly dissolving in KOH. Pileipellis a subcutis to trichoderm, becoming a subcutis when mature. Clamp connections absent. Five species, known from southern China (1), Thailand (2), Mexico (1) and Costa Rica (1). Two separate four gene (nrLSU, tef1, rpb1, rpb2; atp6, tef1, rpb2, cox3) phylogenetic inferences place the genus ambiguously in the Pulveroboletus group near Lanmaoa and Rugiboletus (first inference) and Singerocomus and Rugiboletus (second inference).. Ectomycorrhizae presumed with Fagaceae.

Exsudoporus Vizzini, Simonini & Gelardi (2014) Basidiomata stipitate-pileate, epigeal. Pileus convex to applanate, bright blood red, crimson- red, purplish-red, reddish-pink or reddish-brown, opaque to shiny, dry to subviscid with moist weather, glabrous to subpruinose or subtomentose. Context pale yellow to bright yellow, quickly turning dark blue when injured or exposed, then fading blackish Hymenophore tubulose, adnate or slightly depressed around stipe apex; tubes yellow to olivaceous-brown; pores pinkish-red, reddish- orange, blood red to dark red, rarely yellowish-orange or yellow, often beaded with golden yellow or amber yellow droplets when young and fresh. Stipe central, solid, yellowish to concolorous with the pileus, conspicuously reticulate with elongated, red meshes or deeply reticulate-alveolate. Spores olive-brown in deposit, smooth, subfusiform to ellipsoidal to ellipsoidal-fusoid. Cystidia present. Pileipellis an interwoven trichoderm tending to a cutis. Clamp connections absent. Known from the Northern Hemisphere. Genus phylogenetically inferred for three iconic species (B. frostii, B. floridanus, B. permagnificus). Ectomycorrhizae presumed with Fagaceae

Fistulinella Henn. (=Mucilopilus?) (1901) Pileus dry or viscid, glabrous, fibrillose or tomentose, often scrobiculate, microscopically a trichodermium, cutis, ixotrichodermium, or ixocutis. Context white, unchanging, soft-textured. Stipe dry or viscid, glabrous or pruinose. Spores brownish pink in deposit, smooth, fusoid. Clamp connections absent. Mexico, Caribbean, Brazil, Africa, Asia , Australia, New Zealand, Japan, Indo- nesia. The type species, F. staudtii, needs recollection for phylogenetic inference so that the genus can be interpreted in a modern sense. Compare Mucilopilus (below). Ectomycorrhizae probable for some species with Fagaceae, Nothofagaceae, Leguminosae, Sapotaceae, Myrtaceae; doubtfully present in others.

Gastroboletus Lohwag (1926) The genus appears polyphyletic and circumscribes taxa that have lost the ability to forcibly discharge spores (they are truffle-like, sequestrate). Further, the macromorphology is “reduced” in that the hymenophore is rarely exposed because the pileus does not expand and the stipe does not elongate. These taxa are typically hypogeous to suberumpent. Based on phylogenetic inferences from DNA sequences, this is a polyphyletic genus with alignments in clades of epigeous genera such as Boletus, Xerocomus, Leccinum, and Suillus. The majority have been described from North America, one from Africa, one from Chile, and two from China. There appear to be entities allied to Heimioporus in Australia. Ectomycorrhizae with Fagaceae, Nothofagaceae(?), Pinaceae, legumes(?), Myrtaceae.

Guyanaporus T.W. Henkel & M.E. Smith (2016) Basidiomata epigeous. Pileus grayish brown, dry, tomentulose, trama white to pale yellow, bluing slowly on exposure. Hymenophore tubulose, shallowly depressed at stipe, grayish yellow, bluing slowly with pressure, immature pores nearly stuffed, eventually ovate and angular. Stipe equal, grayish brown, pale yellow at extreme apex, longitudinally striate to reticulate at apex, base densely white tomentose, trama white, unchanging. Basidiospores brownish olive in deposit, smooth, inamyloid. Pleurocystidia present. Cheilocystidia absent. Hymenophoral trama parallel to slightly diverging (phylloporoid), mediostratum barely distinct, concolorous. Pileipellis a trichodermium with variously-shaped terminal elements. Stipitipellis hymenidermous at apex. Clamp connections absent. One species, G. albipodus, from Guyana. True relationships for this genus in the Boletaceae are not apparent. A phylogenetic analysis of the nrLSU and rpb1 places the genus on a long unsupported branch near Tylopilus, Xanthoconium and Imleria. Ectomycorrhizae with Dicymbe (caesalpinoid legume), Pakaraimaea (Cistaceae, formerly in Dipterocarpaceae).

Gymnogaster J.W. Cribb (1956) Basidiomata sequestrate, but stipitate with fertile portion exposed and surrounding percurrent stipe-columella, with pileal disc depressed, dry, dark brown to reddish brown to orangish brown, finely subtomentose. Context yellow, immediately cyanescent. Hymenophore loculose to irregularly poroid, slightly subdecurrent, whitish with some brownish red stains at first, then grayish yellow to olive, immediately cyanescent. Stipe central, tapering downward to a point, dry, deep yellow to orange yellow at apex, red to deep red downward, short sulcate at apex, subpruinose, immediately cyanescent, with interior yellow, immediately cyanescent, becoming hollow. Spores smooth, citriform to amygdaliform, with a germ pore, rarely dextrinoid, rarely cyanophilic. One species known: G. boletoides from SE Queensland, N New South Wales, Australia. Phylogenetic relationships to ballistosporic taxa not completely clear (poorly supported Pulveroboletus group). Probably ectomycorrhizal with Myrtaceae.

Gyrodon Opatowski (1836) Pileus glabrous or rarely subsquamose, dry, microscopically a trichodermium. Context pale yellow to whitish. Hymenophore decurrent, with tubes and pores radially elongated, staining blue. Stipe central to eccentric, often curved and short. Spores olive to olive brown in deposit, smooth, short-ellipsoid to phaseoliform. Hymenial cystidia present to rarely present. Clamp connections present. Widespread, but so far not in Australia. Phylogenetic inference places the genus in the Paxillaceae. Ectomycorrhizae with Alnus; sometimes apparently not (at least in G. exiguus, perhaps others).

Gyroporus Quélet (1886) Pileus dry, glabrous to fibrous-subsquamose, microscopically a trichodermium. Context white to pale yellow, staining blue or brown in some. Hymenophore adnexed, white then pale yellow, with pores staining brown or blue in some. Stipe dry, glabrous or fibrous-subfurfuraceous, hollow or solid, composed of circumferentially arranged hyphae (not longitudinal). Spores yellow in deposit, smooth, ellipsoid. Hymenial cystidia present. Clamp connections present. North Temperate and Pantropical; less common in the southern hemisphere, but widely distributed and diverse in Australia. Phylogenetic placement inferred in Sclerodermatineae, family Gyroporaceae. Ectomycorrhizae with Pinaceae, Fagaceae, Betulaceae, Myrtaceae, Casuarinaceae(?), possibly Lauraceae.

Harrya Halling, Nuhn & Osmundson (2012) Pileus rose pink to brownish pink to pinkish gray. Context white, not staining. Hymenophore tubulose, adnexed, white then vinaceous pink. Stipe white above, chrome yellow at base, beset with fine pink scabers either isolated or rarely arranged on a raised reticulum. Spores pinkish to reddish brown in deposit, smooth, fusoid, dextrinoid in Melzer’s reagent. Hymenial cystidia present. Pseudocystidia absent. Pileipellis a trichodermium. Clamp connections absent. Six species: H. chromapes, H. atriceps plus four others from China (H. alpina, atrogrisea, moniliformis, subalpina). Eastern North America to Central America, China, Japan. Ectomycorrhizae with Pinaceae, Fagaceae, Betulaceae(?).

Heimioporus E. Horak (2004) Pileus dry, rarely subviscid, subtomentose to subvelutinous, even or rarely shallowly alveolate or rarely cerebriform, microscopically a palisadic trichodermium or approaching a hymeniform epithelium. Context white to yellow, not staining or erratically cyanescent near Tubes. Hymenophore adnexed, yellow, sometimes staining blue. Stipe dry, pruinose to reticulate or rarely with sublacerate ridges, with white basal mycelium. Spores olive brown in deposit, alveolate- reticulate to reticulate or with irregular, pit-like perforations, extremely rarely rugulose and with crater-like pits, elongate- ellipsoid to short ellipsoid, lacking a suprahilar plage. Hymenial cystidia present. Clamp connections absent. A sequestrate entity allied to H. cooloolae known from SE Australia. Asia, SE Asia, Australia, Mexico, Belize, and Costa Rica. Ectomycorrhizae with Fagaceae, Dipterocarpaceae, Myrtaceae, Casuarinaceae.

Heliogaster Orihara & K. Iwase (2010) Basidiomata sequestrate (secotioid to gasteroid), hypogeous to nearly epigeous, soft-textured, primarily pale yellow then ochre to light brown. Stipe-columella usually present, forming dendritic sterile tissue. Gleba dry, loculose with empty locules, whitish to grayish white, soon bluish to purplish when cut and exposed. Basidiospores hyaline to pale ochraceous, with pyramidal conical spines, dextrinoid. Hymenial cystidia absent. Peridial surface formed from filamentous interwoven hyphae. Clamp connections absent. Allied to Xerocomellus chrysenteron complex of epigeous boletes according to describing authors (Orihara et al 2010). Morphologically reminiscent of Octaviania. Apparently only in Japan. Ectomycorrhizae expected with Pinaceae and Fagaceae.

Hemileccinum Šutara (2008) Basidiomata pileate-stipitate, recalling Leccinum sect. Luteoscabrum (see Leccinellum below); Pileus dry, subtomentose to glabrous, violet with NH3, with pileipellis a trichodermium or hymeniform. Context yellow or white, unchanging. Hymenophore adnexed, light yellow to deep yellow, unchanging when bruised, with fine pores. Stipe dry, scabrous, with scabers light colored, and barely darkening with age. Spores olive brown in deposit, smooth, fusoid. Hymenial cystidia present. Clamp connections absent. Molecular inferences indicate distinction from Leccinum, Boletus, Xerocomus. Includes 5 species: H. impolitum, H. depilatum in Europe & China, H. subglabripes from E North America & China, and H. indecorum, H. rugosum in China. At least one undescribed from Australia. Ectomycorrhizae with Fagaceae, Betulaceae, Ulmaceae and possibly Myrtaceae in Australia.

Hortiboletus Simonini, Vizzini & Gelardi (2015) Basidiomata pileate-stipitate, recalling Xerocomellus. Spores smooth, not ornamented, with Qm < 2.5, stipe context with small vermillion red dots in the base. Clamp connections absent. Molecular inferences indicate distinction. Northern Hemisphere. Apparently two species from Europe: H. bubalinus, H. rubellus (this latter also N. America). Ectomycorrhizae with Fagaceae(?).

Hourangia Xue T. Zhu & Zhu L. Yang (2015) Basidiomata stipitate-pileate with tubular hymenophore. Pileus hemispherical, convex to applanate, sometimes umbonate; surface densely covered with granular squamules when young, becoming rimose-diffract to small tufted squamulose with age, dry. Context whitish, cream-colored to yellowish, first bluish or indistinctly bluish, then reddish to brownish red, finally brownish to blackish when injured. Hymenophore adnate, sinuate or slightly decurrent; thickness of hymenophore 3–5 (7) times that of pileal context at the position halfway to the pileus center, flesh yellow to dull yellow, staining blue when injured; pores compound, angular; tubes concolorous with hymenophoral surface, staining blue when injured. Stipe central, pale yellow-brown, pale red-brown to dirty pale brown, nearly smooth, sometimes finely fibrillose; context dirty white to yellowish, first typically becoming bluish, then reddish to brownish red, and finally brownish to blackish when exposed; basal mycelia whitish. Pileipellis a trichoderm composed of cylindrical or tumid cells. Hymenial cystidia present. Spores subfusiform, brownish yellow, with bacillate ornamentation (under SEM), rarely only partially ornamented. Clamp connections absent. Known from China, Japan, Indonesia, Malaysia. Phylogenetic inference indicates the genus is sister to Phylloporus with 4-5 species. Ectomycorrhizae presumed with Pinaceae, Fagaceae, Dipterocarpaceae.

Hymenoboletus Y.C. Li & Zhu L. Yang (2016) From the protologue: Basidiomata stipitate-pileate with tubular hymenophore. Pileus hemispherical or convex, subtomentose, dry; context white to cream, without discoloration when injured. Hymenophore depressed around apex of stipe; hymenophoral surface white when young, and becoming pinkish or pink when mature; pores angular or roundish; tubes concolorous with hymenophoral surface, unchanging in color when injured. Stipe central, pink to purplish pink, but yellow to yellowish at apex and bright yellow to chrome yellow at base; basal mycelium chrome yellow. Basidiospores smooth, subfusiform. Pleuro- and cheilocystidia subfusiform to subfusiform- ventricose or clavate. Pileipellis hymeniform. Clamp connections absent. One species (H. luteo- purpureus) phylogenetically inferred in the Zangioideae, between Royoungia-Australopilus and Harrya, but lacks any further phylogenetic support. The single species appears clearly distinct based on microscopic features. Ectomycorrhizae presumed with Fagaceae.

Imleria Vizzini (2014) Basidiomata epigeous. Pileus reddish brown, chestnut brown to dark brick brown, sometimes pallid, minutely to distinctly tomentose when young and dry, soon becoming smooth and polished, viscid in wet weather. Contexts of pileus and stipe whitish to lemon-yellow, becoming blue particularly around the tubes and at the stipe apex when handled. Tubes cream to lemon-yellow, becoming dull yellow with age, bluing on cutting. Pores compound, angular, quite large at maturity, concolorous with tube, bluing when handled. Stipe central, concolorous with pileus or slightly paler, minutely flocculose or fibrillose-striate. Spores boletoid, smooth. Pileipellis an ixotrichoderm, consisting of long, slender and cylindrical interwoven hyphae, smooth to slightly incrusted by a minutely granular, yellowish pigment and embedded in a gelatinous matrix. Clamp connections absent. Northern Hemisphere. One well-known species in N. Hemisphere, I. badia, is inferred from molecular phylogenetics. Three others described from E. Asia; another European one placed here without justification. Ectomycorrhizae presumed with Pinaceae, Fagaceae.

Imperator Koller, Assyov, Bellanger et al. (2015) From the protologue in Index Fungorum 243: Habitus robustissimarum Boletacearum typicus. A gen. Rubroboletus differt pileo tacto caeruleo- dein nigro maculoso, contextum in stipites basi rubropurpureo. Stipes robustum, totaliter reticulato atque flavo-purpurascens. Pori minuti, primitus lutei vel rubri, tacto cærulescentibus. Caro compacta, odore fortis, flavo-sulphurea, virescens deiunque fracta caerulescens; stipite basi. Holotype: Boletus torosus Fr. 1835. Phylogenetic results based on ITS and 28S rDNA sequences reveal that the three species cited above (I. luteocupreus, I. rhodopurpureus, I. torosus) belong to a monophyletic lineage, not characterized in earlier works (Nuhn et al. 2013, Fungal Biology 117: 479-511; Arora & Frank 2014, Mycologia 106(3): 464-480; Gelardi et al. 2014, Mycologia 106 (6): 1168-1187; Simonini & Vizzini 2014, Mycol. Progress 13(1): 95-109; Wu et al. 2014, Fungal Diversity on line, DOI: http://dx.doi.org/10.1007/s13225-014-0283-8; Wu et al 2015, Fungal Diversity on line, DOI: 10.1007/s13225-015-0322-0). The three species identified in this clade are all European, known from broadleaved forests on calcareous soils. This group is characterized by a unique combination of features: yellow to reddish-orange reticulate stipe, staining dark purplish red from base with age, a typical blue to blackish staining on pileus surface when touched, and an intense bluing reaction of the context when cut. Pores are either yellow, red or purplish with a high chromatic variability of all parts of basidiome in I. rhodopurpureus. Phylogenetic results supporting this publication (ITS and 28S ML phylogenetic trees) are accessible online at http://boletales.com/phylogenetics/.

Indoporus Parihar, Das, Hembrom & Vizzini (2018) Based on the protologue: Basidiomata epigeous; pileus gray with black squamules, dry, with yellowish white context, quickly dull red to grayish red then eventually black when exposed. Hymenophore tubulose, depressed around stipe, reddish gray or brownish orange when bruised, eventually black, with simple angular pores. Stipe smooth, grayish violet above, gray to blackish brown below, with context grayish violet to dark violet above, dark blackish brown below becoming black when exposed. Spores grayish brown in deposit, smooth, inamyloid. Pleurocystidia hyaline and rare; cheilocystidia hyaline and common. Pileipellis a trichoderm, with hyphae containing blackish brown pigment, sometimes with zebroid incrustations. Clamp connections? The type species I. shoreae was described from Jharkhand, India based on several specimens. Molecular phylogenetic analyses based on nrLSU, ITS, and rpb2 infer an independent clade sister to Afroboletus and Imleria pallida (LSU, rpb2 with no support) and Chalciporus and Buchwaldoboletus (ITS with less than 70% support). Ectomycorrhizae with Dipterocarpaceae (Shorea robusta) probable.

Ionosporus Khmelnitsky (2019) Basidiomata epigeous, dry, dark gray to sooty gray brown on pileus and stipe; hymenophore tubulose with angular pores, whitish to grayish yellow to pale greenish yellow, staining red when bruised; stipe usually central, finely but conspicuously reticulate and densely finely subpruinose, concolorous with pileus, conspicuously white at the base; context white or very pale yellow, unchanging when exposed. Spores pale violet to reddish brown in deposit, deeply purple-violet in dilute KOH solutions, dextrinoid in Melzer’s Reagent, fusoid to elongate, appearing smooth with bright field light microscopy, barely granulose with Nomarski DIC optics, irregularly and finely granulose to pitted granulose with SEM, sometimes with a faint germ pore. Pileipellis a trichodermium. Clamp connections absent. Peninsular Malaysia, E Australia; two species: I. longipes, I. australis. Molecular phylogenetics infers placement in Leccinoideae near Borofutus, Rhodactina, and Spongiforma. Ectomycorrhizae presumed with Dipterocarpaceae, Myrtaceae, Casuarinaceae.

Jimtrappea T.W. Henkel, M.E. Smith & Aime (2015) Distinguished by morphological features (and sequestrate habit), including molecular inference as allied to Tylopilus. See latter for morphological features. One species from Guyana. Ectomycorrhizae with caesalpinoid legumes (Dicymbe, Aldina).

Kombocles Castellano, T.W. Henkel, & Dentinger (2016) Basidiomata sequestrate, emergent and (sub-)globose, firm, becoming brownish. Gleba loculate, with white tramal veins, with brown locules. Columella absent. Spores asymmetrical, fusoid to allantoid to unevenly ellipsoid, yellow brown, rugulose, dextrinoid. Hymenial cystidia and clamp connections absent. One ribosomal gene (28S) inferred placement near Heimioporus with very low bootstrap support. One species, K. bakaiana, from Cameroon. Ectomycorrhizae presumed with Uapaca.

Lanmaoa G. Wu, Zhu L. Yang & Halling (2015) Basidiomata stipitate-pileate. Pileus hemispherical, convex or applanate, subtomentose, dry, slightly incurved at the margin when young. Context off-white to cream yellow, slowly staining pale blue to light blue when injured. Hymenophore adnexed or sinuate, thin (1/3–1/5 thickness of context midway from disc to margin), cream yellow to lemon yellow, staining dull blue when injured with tubes concolorous with hymenophoral surface or light red, staining dark blue when injured with pores angular or nearly round. Stipe central, cream yellow, light yellow to lemon yellow at the apex and light to dark purple red towards the base with basal mycelia yellowish white to white. Pileipellis often an interwoven trichodermium to subcutis, rarely ixosubcutis. Hymenial cystidia present. Spores smooth, narrowly suboblong to subfusoid, light yellow to brownish yellow. Clamp connections absent. Eastern Asia, eastern North America, Central America. Ectomycorrhizae presumed with Pinaceae, Fagaceae.

Leccinellum Bresinsky & Manfr. Binder (2003) Accommodates most of the taxa with yellow hymenophore formerly placed in Leccinum sect. Luteoscabrum (but see Hemileccinum above). This includes several European taxa (e.g., L. nigrescens, carpini, corsicum, crocipodium, griseum, lepidum, & luteoscabrum, and L. quercophilum from E N America). Apparently restricted to the Northern Hemisphere (Europe, E North America, E Asia). Ectomycorrhizae with Fagaceae, Betulaceae.

Leccinum S. F. Gray (1821) Pileus viscid or dry, glabrous to subtomentose, microscopically a trichodermium or hymeniform. Context white or pale yellow, unchanging or staining red, pink, gray, or blue to blue- green. Hymenophore adnexed, white to tan to yellow, often staining pale brown. Stipe dry, scabrous, with scales whitish at first becoming brown to black. Spores brown (olive brown?) in deposit, smooth, fusoid. Hymenial cystidia present. Clamp connections absent. North Temperate, montane Neotropics, Asian and African tropics. In Australia as exotic import associated with horticultural plantings (Betula, Quercus) fide Watling & Gregory (1988); likewise in New Zealand (McNabb 1968). Ectomycorrhizae with Pinaceae, Fagaceae, Betulaceae, caesalpinoid legumes.

Longistriata Sulzbacher, Orihara, Grebenc, M.P. Martín, Baseia (2020) Basidiomata sequestrate, hypogeous to subhypogeous, subglobose with short stipe. Peridium bright yellow, smooth with an interwoven cutis and inflated gelatinous hyphae. Gleba is loculate, white to yellowish brown staining dark green to black with age, lacking a columella. Basidiospores broadly ellipsoid, hyaline in alkali, dextrinoid, with thin, irregular longitudinal ridge, sometimes anastomosed. Cystidia lageniform. Clamp connections absent. One species known from northeastern Brazil. nrLSU and tef1 inferences indicate alliance with Mackintoshia. Ectomycorrhizae presumed with Coccoloba, and Guapira.

Mackintoshia Pacioni & Sharp (2000) Basidiomata sequestrate, hypogeous, subglobose to pyriform. Peridium well developed, pale yellow to orange yellow wit rusty colored cracks. Gleba white to ochraceous to olivaceous, soft and rubbery with gelatinous tramal plates, gel-filled at maturity. Spores smooth, elliptical, slightly thick- walled, sometimes reported with a germ pore. Hymenial cystidia with dense, yellow, cyanophilous content, thin-walled. Clamp connections absent. Odor fruity. So far, only one species, M. persica, reported from Zimbabwe. 28s and ITS infer placement near Parvixerocomus in the Boletoideae. Ectomycorrhizae presumed with caesalpinoids, Brachystegia and Burkea.

Melanogaster Corda (1831) Basidiomata sequestrate, usually hypogeous. Peridium well developed, dry, slightly pruinose, ochre to ochraceous yellow to reddish brown, sometimes with adherent rhizomorphs. Gleba gel-filled at maturity, whitish at first then dark brown to black at maturity, lacking well-developed hymenium, with whitish to yellowish tramal plates, lacking a sterile base and columella. Spores smooth, dark brown, orthotropic, with well-developed sterigmal appendage, ovoid to ellipsoid, fusoid to limoniform. Clamp connections present. Northern Hemisphere, Central America. Phylogenetic inference places the genus in the Paxillaceae. Ectomycorrhizae presumed with Pinaceae, Fagaceae, Betulaceae.

Mucilopilus Wolfe (1979) The genus is based on Porphyrellus viscidus, described by McNabb from New Zealand. Five other species were placed here by Wolfe. Some, including the type species, were incorporated earlier in Fistulinella (q.v.) by Singer, and another was moved to Veloporphyrellus (V. conicus) based on molecular phylogenetic analyses. Only M. castaneiceps and M. mexicanus have not been transferred. If the type species is truly a Fistulinella, then the genus becomes a synonym of that genus and some other generic name is needed for castaneiceps and mexicanus. Refer to Fistulinella for features.

Mycoamaranthus Castellano, Trappe, & Malajczuk (1992) Basidiomata sequestrate, bright chrome yellow to orange yellow, dry, glabrous to squamulose, globose to subglobose, with numerous rhizomorphs. Gleba viscid to spongy-gelatinous to rubbery, variously colored at first, but darker (grayish-brownish) at maturity. Spores ovoid to obpyriform, with apparent germ pore at apex, pedicillate, spinose to minutely verrucose. Clamp connections absent. Zimbabwe, Malawi, Congo-Kinshasa, Cambodia, Thailand, Malaysia, Singapore, Australia. Ectomycorrhizae with Dipterocarpaceae, Myrtaceae (Eucalyptus, Syncarpia), Allocasuarina, Brachystegia, Julbernarida, Uapaca.

Neoboletus Gelardi, Simonini & Vizzini (2014) Basidiomata stipitate-pileate with tubular hymenophore, epigeal, evelate. Pileus convex to applanate, bay-brown, date-brown, olive-brown, reddish-brown to blood red, ochraceous or yellow, opaque, dry, velvety to subtomentose. Context firm, pale yellow to bright yellow, quickly turning dark blue when injured or exposed. Hymenophore tubulose, adnate or slightly depressed, with tubes yellow to olivaceous-brown, with pores reddish-orange, blood red to reddish-brown, yellowish- orange or yellow. Stipe central, solid, yellowish, ornamented by conspicuous reddish to reddish- brown or yellow punctuations throughout or at least in the upper part, sometimes reticulate, with or without strigose base. Spores olive-brown in deposit, smooth, subfusiform to ellipsoidal to ellipsoidal-fusoid. Cystidia present. Pileipellis a subparallel or interwoven trichoderm tending to a cutis. Clamp connections absent. North Temperate. Ectomycorrhizae presumed with Pinaceae, Fagaceae.

Nigroboletus Gelardi et al. (2015) Original diagnosis: Basidiome stipitate–pileate with tubular hymenophore, epigeal, evelate, medium–small sized; pileus convex to applanate, subtomentose to glabrous; hymenophore very thin, poroid, adnate to subdecurrent, yellow to olive–yellow; stipe solid, dry, smooth to minutely pruinose- punctate, reticulation absent; context firm, yellowish; tissues turning dull grayish to blackish throughout when injured or exposed; taste mild; spore print olive–brown; spores smooth, broadly ellipsoid to subovoid; pleuro–, cheilo–, and caulocystidia present; pileipellis consisting of subparallel to loosely interwoven erect hyphae; hymenophoral trama bilateral–divergent of the Boletus–type or intermediate between the Boletus–type and the Phylloporus–type; lateral stipe stratum of the boletoid type; clamp connections absent; ontogenetic development gymnocarpic. Molecular phylogenetic inference places the single known species, N. roseonigrescens, in the Boletoideae near Xerocomellus. Currently only known from tropical SE China. Ectomycorrhizae presumed with Fagaceae (Castanopsis, Castanea, Lithocarpus).

Octaviania Vittadini (1831) Basidiomata sequestrate, frequently hypogeous, or more rarely emergent. Peridium persistent, glabrous to floccose or warty to scaly, often discoloring when bruised. Gleba whitish at first, marbled, becoming brown to black at maturity, dry to gelatinized. Spores globose to ellipsoid, beset with thick, conspicuous, pyramidal to conical projections (warts?) sometimes fused to form irregular ridges, dextrinoid. Sterile base absent or present. Clamp connections absent. North America, Europe, Asia, Australasia. Ectomycorrhizae presumed with Pinaceae, Fagaceae, Betulaceae, Nothofagaceae, Myrtaceae, Casuarinaceae.

Paragyrodon (Singer) Singer (1942) Pileus viscid, microscopically an ixocutis. Context white to yellowish, staining brown. Hymenophore adnate to decurrent, bright yellow then brown, staining bright brown. Peronate veil present, forming an annulus. Stipe central to eccentric. Spore deposit olive to mustard brown. Spores smooth, globose to subglobose. Hymenial cystidia present. Clamp connections present. Well-known species in north central North America, P. sphaerosporus. Ectomycorrhizae with Quercus suspected but not confirmed. Phylogenetic inference places the genus in the Paxillaceae.

Parvixerocomus G. Wu & Zhu L. Yang (2015) Based on the protologue: Basidioma stipitate-pileate with tubular hymenophore, small. Pileus convex to applanate, subtomentose, dry; context yellowish to yellow, staining blue immediately when injured. Hymenophore subdecurrent, often with teeth on the apex of stipe; hymenophoral surface yellowish to yellow, staining blue immediately when injured; pores irregular, angular to nearly round, often compound; tubes concolorous with hymenophoral surface, staining blue immediately when injured. Stipe central, light brown, brownish red to reddish brown, surface often pruinose; basal mycelia cream to grayish yellowish. Pileipellis an epithelium composed of submoniliform to moniliform hyphae with cystidioid terminal cells. Pleuro- and cheilocystidia subfusiform-ventricose or clavate, with subacute apex or with long beak. Basidiospores smooth, ovoid to ellipsoid, yellowish to brownish yellow. Clamp connections absent. Phylogenetic inference places the genus in the Boletoideae near Xerocomellus. Two species known from China and Japan. Ectomycorrhizae presumed with Fagaceae and possibly Pinaceae.

Paxillogaster Horak (1966) Basidiome epigeous, pyriform to lycoperdon-like, dry, not expanded, with interwoven hyphae in the epicutis. Gleba loculose to sublamelliform, typically enclosed, rarely exposed. Stipe well developed, with fragmented veil absent. Spores bilaterally symmetric, fusoid to inequilaterally ellipsoid, smooth but with exosporium indistinctly perforate, yellow. Cystidia claviform, Clamp connections absent. One species known, P. luteum, from Antarctic beech forests in Argentina. Ectomycorrhizae presumed with Nothofagus dombeyi, pumilio, antarctica.

Phlebopus (Heim) Singer (1936) Pileus dry to subviscid, glabrous, microscopically a trichodermium. Context white or pale yellow, unchanging or staining blue. Hymenophore adnate, tubulose, staining blue or not. Stipe dry, glabrous. Spores olive brown in deposit, smooth, short-ellipsoid. Hymenial cystidia sometimes present. Clamp connections present. Pantropical and subtropical to south temperate (Australia. Brazil, central Africa. SE Asia). Ectomycorrhizae absent or possibly facultative with legumes. Some associated with Insects (aphids).

Phylloboletellus Singer (1952) Pileus dry, convex, yellow becoming yellowish brown to orangish brown. Context yellowish, cyanescent near lamellae. Taste bitter. Hymenophore lamellate, adnate to decurrent, sometimes forked, yellowish green becoming olive brown, cyanescent. Spores olive brown in deposit, ovoid, longitudinally winged/ridged, inamyloid. Clamp connections mostly absent; some aborted. Known from Mexico and Argentina. Ectomycorrhizae apparently not formed.

Phyllobolites Singer (1942) Pileus viscid but soon dry, red, glabrous. Lamellae deeply decurrent, scattered intervenose, forking once or twice, pallid. Stipe dry, central, terete, pallid staining pale brown. Veil present, forming a narrow annulus at stipe apex, somewhat fugacious and easily overlooked. Context white, unchanging. Spores fusoid to fusoid-ovoid, longitudinally rugose with rows of coarse warts and short ridges, inamyloid. Hymenial cystidia absent, but pseudocystidia present. Clamp connections present. In need of recollection and sequencing. Originally described from Amazonas, Brazil under leguminous trees, and placed in the Paxillaceae.

Phylloporopsis Angelini et al. (in Farid et al. 2018) From the original diagnosis: Basidiomata pileate-stipitate with lamellate to subporoid hymenophore, epigeal, evelate, medium-small sized; pileus convex to applanate, velvety-tomentose to fibrillose; hymenophore lamellate to subporoid with anastomosing and intervenose gills, strongly decurrent, beige to olive-cream or olive buff; stipe solid to sometimes hollow at maturity, dry, pruinose to longitudinally fibrillose, reticulation absent; basal mycelium whitish to yellowish, context firm, whitish but cream-yellowish in the stipe; tissues unchangeable or turning light blue especially on hymenophore and pileus context when injured or exposed; taste mild to slightly bitter; olive-brown spore print; purplish-pink or reddish reaction with ammonia on pileus cuticle; basidiospores smooth, ellipsoid- fusiform, spore wall cyanophilic; pleuro-, cheilo and caulocystidia present; pileipellis a trichodermium; hymenophoral trama bilateral-divergent of the “Phylloporus-type”; lateral stipe stratum absent; clamp connections absent; ontogenetic development gymnocarpic. According to the phylogenetic analysis of the combined ITS, 28S, TEF1-α, and RPB1 sequences the genus is unrelated to Phylloporus and sister to Bothia and Solioccasus (Bothia clade); part of a polytomy in the Boletoideae. One species, P. boletinoides, found in Central America, Caribbean, and eastern-southeastern USA. Ectomycorrhizae presumed with Pinaceae and Fagaceae.

Phylloporus Quélet (1888) Pileus dry, tomentose to subtomentose, microscopically a trichodermium or a modified hymeniform layer. Context usually white, sometimes yellow, sometimes changing to blue when exposed. Hymenophore lamellate to subtubulose to radically boletinoid, sometimes changing to blue when bruised. Stipe central, rarely slightly eccentric, usually pruinose; basal mycelium white or yellow (IMPORTANT!). Spores olive brown in deposit, smooth, fusoid or ovoid, dextrinoid.

Hymenial cystidia present. Clamp connections absent (present in 1 or 2 species). NH3 reactions negative or positive (blue or blue green, sometimes pinkish lilac or rarely other colors – IMPORTANT!). Mostly tropical, but some temperate (north and south) taxa. Ectomycorrhizae with Pinaceae, Fagaceae, Myrtaceae, Dipterocarpaceae, Casuarinaceae.

Porphyrellus E.-J. Gilbert (1931) This genus used for the typically, somber colored taxa originally placed in Tylopilus with very dark brown to dark pinkish brown colored spore print. They are often cyanescent and/or rufescent and then nigrescent. The hymenophore is usually not pinkish vinaceous with maturity, but might be a pale greenish yellow becoming black. Based on the European P. pseudoscaber nom. inval. (= P. porphyrosporus). A distinct genus inferred from DNA sequences. Further taxon discovery and phylogenetic inference should help clarify generic boundary. Many north temperate (one in Europe, several in North America, E Asia), and possibly a few in Australia, New Zealand; these latter may be generically distinct based on molecular inference. Ectomycorrhizae presumed with Pinaceae, Fagaceae, Myrtaceae, Casuarinaceae, perhaps Dipterocarpaceae, Nothofagaceae, caesalpinoid legumes.

Pseudoaustroboletus Y.C. Li & Zhu L. Yang (2014) Basidiomata stipitate-pileate with tubular hymenophore. Pileus hemispherical to applanate, not viscid when wet, with radially arranged filamentous squamules. Context white to pallid, unchanged in color when injured, but occasionally with yellowish discoloration on the base of the stipe. Hymenophore adnate to depressed around apex of stipe, white to pallid when young, and becoming pale pinkish or pinkish to pink when mature, unchanged in color when injured. Stipe pallid to white, reticulate with elongate meshes. Basal mycelia white. Pileipellis an interwoven trichoderm. Hymenial cystidia with brown to dark brown vacuolar pigment. Spores pinkish to pink in deposit, smooth, pinkish to light olivaceous to nearly colorless. Clamp connections absent. Currently known from Japan, China, Malaysia, Singapore. One species, with two varieties. NOTE: Despite the generic name, the genus is not close to Austroboletus; rather based on the molecular inference, it is most nearly allied to Tylopilus (nrLSU) or a Leccinoideae clade (combined nrLSU, t ef1, mtSSU). Ectomycorrhizae apparently with Fagaceae.

Pseudoboletus Šutara (1991) An epigeous bolete with xerocomoid habit that is associated with Scleroderma and Astraeus. Northern hemisphere. Considered parasitic, but one of the pair is ectomycorrhizal.

Pulchroboletus Gelardi, Vizzini & Simonini (2014) Original diagnosis: Differing from Alessioporus by the pastel pink, cream-pinkish to whitish pink or rarely blood red pileus surface, the smooth to densely punctuate stipe surface, rarely with a coarse reticulum, the pseudo-annulus usually located in the upper or middle part of the stipe, the pinkish lilac context of the pileus and unique ITS, LSU and tef-1α sequences. Apparently aligned in the Xerocomoideae and circumscribes just two species, one in Mediterranean Europe and the other in states along the Gulf Coast, USA. Ectomycorrhizae presumed with Fagaceae (Quercus, Castanea), possibly Cistus.

Pulveroboletus Murrill (1909) Pileus dry or barely subviscid, glabrous or sometimes scaly, microscopically a collapsed trichodermium. Context white to pale yellow, slowly staining blue. Hymenophore adnate to adnexed, yellow, staining blue. Peronate veil present, collapsing to form annular zone or coarse scabers. Stipe dry to sticky, apparently glabrous or sometimes scaly. Spore deposit olive brown. Spores smooth, fusoid. Hymenial cystidia present. Clamp connections absent. North America, East Asia, Southeast Asia, Australia, Africa, montane Neotropics. Ectomycorrhizae with Fagaceae, Myrtaceae, Casuarinaceae, Pinaceae(?), possibly Dipterocarpaceae, caesalpinoid legumes.

Retiboletus Binder & Bresinsky (2002) Recognized as distinct from Boletus. In research published by V. Hellwig, the genus produces a unique group of butenolide compounds called retipolides (rarely without) that are responsible for the bitter taste and the intense yellow color of the context. Spores olive brown in deposit, fusoid, smooth. Hymenial cystidia present. Clamp connections absent. Circumscribes 12 northern hemisphere species with conspicuously reticulate stipes. Temperate New World (Japan?) to montane Neotropics. Ectomycorrhizae with Fagaceae.

Rheubarbariboletus Vizzini, Simonini & Gelardi (2015) From the original diagnosis: Differs from Xerocomellus by the spores smooth in all species, never striate, never truncate, elements of the pileipellis smooth or only with finely incrusting pigment, the presence of congophilous plaques on hyphal surface, the tapered and rooting stipe base, the bright yellow-ochraceous to orange-rhubarb and unchangeable context in the stipe base, and the dark blue- green to blackish reaction with iron sulphate on pileus surface and in the stipe base context. Apparently restricted to Europe. Ectomycorrhizae presumed with Fagaceae, Pinaceae.

Rhizopogon Fries (1817) Basidiomata sequestrate, hypogeous to erumpent. Peridium dry, pruinose to subtomentose, sometimes with overlaying rhizomorphs, sometimes bruising, white to yellow to brown to reddish brown. Gleba dry, minutely loculose, whitish at first, eventually brownish, lacking a columella. Spores smooth, ellipsoid to fusoid, hyaline to pale yellowish, rarely globose and reticulate. Clamp connections absent. Northern Hemisphere. Often present where Pinaceae introduced (e.g., Australia, New Zealand, South America). Ectomycorrhizae with Pinaceae.

Rhodactina Pegler & T.W.K. Young (1989) Basidiomata sequestrate, globose to pyriform, white with a silky sheen and drab gray tinges, bruising brownish gray to dark brown. Gleba enclosed, loculose, vinaceous at first, then soon pale cinnamon to avellaneous, with empty locules. Stipe absent but with a sterile basal pad. Spores reddish purple, broadly ellipsoid to subfusoid, longitudinally costate, with 6-10 ribs, dextrinoid. Peridial pellis repent, with fine to coarse encrustations. Clamp connections absent. Phylogenetic relationships inferred from atp6, tef1, and rpb2 sequences indicate placement in subfam. Leccinoideae near Ionosporus, Borofutus and Spongiforma. Three species known from India and Thailand. NOTE: there appear to be epigeous entities in SE Asia (Viet Nam, Thailand, Malaysia) with similar spore morphology. One species is well-described as Afroboletus vietnamensis by T.H.G. Pham et al. Ectomycorrhizae presumed with Dipterocarpaceae (at least Shorea robusta).

Rossbeevera T. Lebel, Orihara (2012) (originally Rosbeeva) Basidiomata sequestrate, flattened to globose or subglobose, sometimes slightly cerebriform, white or rarely pink developing greenish blue colors in situ, sometimes slowly staining bluish or greenish blue when handled or on exposure. Gleba finely loculose, without gel-filled chambers, white at first, becoming cinnamon to dark brown with maturity. Rhizomorphs present at a sterile base. Spores pale brown to dark brown, ellipsoid to broadly fusoid, smooth but with 3–5 longitudinal ridges, angular to stellate in polar view. Clamp connections absent. A sequestrate genus described by Lebel et al (2011) allied to Leccinum, it is a western Pacific entity with species formerly placed in the north temperate Chamonixia. Distinction is primarily supported by molecular inferences and spore morphology. Australia, New Zealand, Singapore, Borneo, China, Japan. Ectomycorrhizae presumed with Eucalyptus, Leptospermum, Syncarpia, Allocasuarina, Acacia, Castanopsis, Quercus, Fagus, Nothofagus.

Royoungia Castellano, Trappe & Malajczuk (1992) Basidiomata gasteroid (sequestrate), flattened to globose or subglobose, bright golden yellow to dull orange, dry. Gleba loculose, somewhat cartilaginous, chocolate brown or a sordid yellow in color when mature, with empty locules. Rhizomorphs numerous, concolorous with peridium. Columella absent or sometimes present as a basal pad, white, or nearly concolorous with peridium, erroneously described as staining bright red (in the type species). Spores subfusoid, smooth. Peridial pellis compactly interwoven. Trama divergent, gelatinous. Clamp connections absent. Eastern Australia (Queensland, New South Wales, Tasmania, Victoria). Ectomycorrhizae presumed with Myrtaceae (Eucalyptus, Leptospermum, Melaleuca), Casuarinaceae (Allocasuarina).

Rubroboletus Zhao & Zhu L. Yang (2014) Basidiomata stipitate-pileate. Pileus hemispherical, convex or applanate, grayish, pinkish to red. Context white, yellowish to lemon-yellow, cyanescent. Hymenophore surface orange red to blood red, sometimes orange-yellow when mature, rapidly bluing when bruised. Tubes yellow to olivaceous green, cyanescent when injured, then back to the original color slowly. Stipe central, covered with pinkish, red to brownish red reticula or spots. Pileipellis an interwoven trichoderm composed of more or less vertically arranged, sometimes gelatinized filamentous hyphae. Hymenophoral trama boletoid. Basidiospores smooth, subfusiform to ovoid-ellipsoid, slightly thick-walled. Hymenial cystidia present. Clamp connections absent. [Adapted from Zhao et al 2014]. China, Europe, North and Central America. Ectomycorrhizae presumed with Pinaceae, Fagaceae.

Rugiboletus G. Wu & Zhu L. Yang (2015) Basidiomata stipitate-pileate. Pileus hemispherical, convex or applanate, subtomentose, dry, strongly wrinkled (especially when young), usually with incurved or extended margin. Context cream, light yellow to yellow, unchanging or staining light blue slowly when bruised. Hymenophore adnexed to adnate, light yellow, yellow, or brown, reddish brown to yellowish brown, unchanging or staining blue to dark blue quickly when bruised, with tubes grayish-yellowish, brownish yellow, unchanging or staining blue, dark blue to greenish blue quickly when bruised, with pores nearly round to round. Stipe central, light yellow to yellow, covered by minute squamules, with basal mycelia off-white to light yellow. Pileipellis an ixotrichodermium to an interwoven ixotrichodermium. Hymenial cystidia present. Basidiospores smooth, subfusiform, brownish yellow. Clamp connections absent. Eastern Asia (China, Japan, far east Russia, Korea, Nepal, Thailand) and possibly Central America, Colombia. Ectomycorrhizae presumed with Pinaceae, Fagaceae.

Singerocomus T.W. Henkel & M.E. Smith (2016) Basidiomata epigeous. Pileus pinkish red to red, tomentose, trama white to light yellow, unchanging. Hymenophore tubulose, depressed at stipe, yellow, unchanging, pores subangular. Stipe equal, concolorous or lighter, glabrous or with squamules and scales, base yellow dull yellow tomentose, trama white to light yellow. Basidiospores olivaceous brown in deposit, smooth, inamyloid. Pleurocystidia present. Cheilocystidia present or absent. Hymenophoral trama parallel to slightly divergent (phylloporoid). Pileipellis a trichodermium, terminal cells cylindrical. Clamp connections absent. Inference suggests a long-branch sister relationship with E. Asian Rugiboletus based on 28S and RPB1 genes. Two species known from Brazil and Guyana. Ectomycorrhizae with caesalpinoid legumes (Aldina, Dicymbe) in Guyana and Nyctaginaceae in Brazil.

Singeromyces Moser (1966) Basidiomata hypogeous, lacking a peridium, with percurrent columella. Gleba irregularly lacunose, ferruginous. Spores honey yellow, ellipsoid-cylindric, punctate-perforate. Cystidia absent. Clamp connections absent. One species, S. ferrugineus, known Puerto Manzano, Argentina. Ectomycorrhizae presumed with Nothofagus pumilio.

Solioccasus Trappe, Osmundson, Manfr. Binder, Castellano & Halling (2013) Basidiomata gastroid (sequestrate), hypogeous or emergent, subglobose to lobed and irregular in outline, arising from yellow to orange to red rhizomorphs, often wrapped with copious, flattened rhizomorphs, dry, with peridium soon evanescent, exposing loculose gleba, whitish when young, soon yellow to orange to red. Gleba loculose, developing yellow to orange to red colors, with a prominent to inconspicuous, dendroid, cartilaginous columella. Spores pale yellow, smooth (light microscope), faintly and irregularly roughened (Nomarski DIC, SEM), ellipsoid or rarely subangular to subfusoid, inamyloid. Clamp connections absent. Papua New Guinea, Australia (Queensland, Northern Territory). Ectomycorrhizae with Myrtaceae (Corymbia, Eucalyptus, Leptospermum, Lophostemon, Melaleuca), Casuarinaceae (Allocasuarina).

Spongiforma Desjardin, Manfr. Binder, S. Roekring & Flegel (2009) Basidiomata epigeous, sessile, cerebriform to sponge-like, rubbery-gelatinous; peridium absent. Gleba with locules 2-20 mm broad, irregular in outline. Columella poorly developed, pyriform, cream-colored, attached to white rhizomorphs. Spores brown to vinaceous brown in mass, amygdaliform, bilaterally symmetrical, rugulose, with an apical pore or depression, reddish brown in water, violet gray in hydroxide, inamyloid, cyanophilic. Cystidia common. Tramal hyphae gelatinous. Clamp connections absent. Molecular phylogenetic inference (tef1, atp6, rpb2) suggests placement in the Boletaceae (subfam. Leccinoideae) near Ionosporus, Borofutus and Rhodactina). Two species known from Thailand, Borneo. Ectomycorrhizae presumed with Dipterocarpaceae (Shorea, Dipterocarpus)

Spongispora G. Wu, S.M.L. Lee, E. Horak, Zhu L. Yang (2018) Description from protologue: Basidiomes stipitate-pileate with tubular hymenophore. Pileus convex or plano-convex, surface dry, subtomentose to squamulose, in age often cracked into isolated squamules; context whitish to cream, very slowly staining pale brown after exposure. Tubes adnexed, concolorous with pores when young, becoming yellowish brown to light brown with age, not narrow. Pores roundish to irregular-angular, cream colored when young, becoming apricot yellow to grayish orange with age, staining brownish to brown where bruised. Stipe central, coarsely reticulate to reticulate; context whitish to cream in the upper part, pale yellow in lower half, slowly staining pale brown to light brown on exposure. Basidiospores nearly elliptical to ovoid, with surface irregularly warty under light microscopy but with sponge-like perforated exospore under SEM. Pleurocystidia and cheilocystidia subfusiform-ventricose, sometimes with apical beak. Pileipellis an interwoven trichodermium. Clamp connections absent. One species known from the Singapore Botanic Garden (S. temasekensis). Robust molecular phylogenetic signal places this genus in the Leccinoideae on a long branch basal to Leccinum, Leccinellum, Octaviania, Turmalinea, and Rossbeevera. Ectomycorrhizae with Hopea odorata (Dipterocarpaceae).

Strobilomyces Berkeley (1851) Pileus dry, coarsely fibrillose to squamulose, black, infrequently dark brown, very rarely pale yellow, often with appendiculate veil remnants, microscopically a trichodermium. Context white, staining reddish orange to dull reddish then black, or sometimes slowly blackening straightaway with only a hint of the reddish tints. Hymenophore adnexed to adnate, sometimes with subdecurrent lines, white then black, staining red then black or sometimes slowly black straightaway. Peronate veil present or sometimes absent and then remains hanging from Pileus margin. Stipe dry, squamose, sometimes annulate, white to gray to black. Spores black in deposit, globose, reticulate to irregularly echinate or sparrasoid to cristate. Hymenial cystidia present. Clamp connections absent. North Temperate Zone, montane Neotropics, Southeast Asia, Australia. Some African representatives have been transferred to Afroboletus. Ectomycorrhizae with Pinaceae, Fagaceae, Myrtaceae, Casuarinaceae(?), Dipterocarpaceae, Caesalpinoid legumes.

Suillellus Murrill (1909) Pileus surface glabrous or nearly so, dry or slightly viscid. Context white or yellow, fleshy, very firm, cyanescent. Tubes usually free, small, yellowish within, their mouths closed when young, and red or orange from the first, not covered with a veil, cyanescent. Stipe solid, usually reticulated or dotted. Spores oblong-ellipsoid, smooth, yellowish-brown, sometimes with greenish tints. Clamp connections absent. North Temperate. Ectomycorrhizae assumed with Pinaceae, Fagaceae. NOTE: This genus circumscribes a portion of the original Boletus subsect. Luridi (those with red pores). See also Caloboletus, Crocinoboletus, Exsudoporus, Neoboletus, and Rubroboletus.

Suillus S.F. Gray (1821) Pileus viscid and glabrous or dry and squamulose, sometimes with appendiculate remnants, microscopically an ixotrichodermium or a trichodermium. Context white or pale yellow, unchanging or sometime staining a pale reddish. Hymenophore adnate to adnexed, yellow or pale cinnamon brown. Stipe dry, annulate or not, typically with glandular dots or smears. Spore deposit pale cinnamon brown. Spores smooth, short fusoid. Hymenial cystidia usually clustered, with amorphous brown pigmentation at the base. Clamp connections absent. North Temperate and southward into the tropics to the southern limit of Pinaceae (S. subaureus with Betula). Absent in Africa. Frequently occurring with exotic Pinaceae transplanted beyond natural range. Obligate ectomycorrhizae with Pinaceae but one known with Betula in NE USA.

Sutorius Halling, Nuhn & Fechner (2012) Pileus dry, rarely viscid (wet weather), very finely matted, brown to chocolate brown to violet brown. Context white and mottled brownish lilac, unchanging. Hymenophore adnexed, lilac to pale brown to violet brown. Stipe dry, with scissurate fine scales, lilac brown to violet brown. Spore deposit reddish brown. Spores ellipsoid to subfusoid, smooth. Hymenial cystidia present, scattered. Pileipellis a trichoderm. Clamp connections absent. Africa; E & SE Asia; Indomalaya; North & Central America; northern South America; Australia. Ectomycorrhizae with Myrtaceae, Casuarinaceae, Fagaceae, Dipterocarpaceae, Pinaceae, Caesalpinoid legumes.

Tengioboletus G. Wu & Zhu L. Yang (2016) From the protologue: Basidiomata stipitate-pileate with tubular hymenophore. Pileus convex or applanate, glabrous to subtomentose, dry, sometimes viscid when wet; context yellowish to yellow, color unchanging when cut. Hymenophore adnate to sinuate; hymenophoral surface white when young, yellowish to yellow when mature, color unchanging when injured; pores roundish; tubes concolorous with hymenophoral surface, color unchanging when injured. Stipe central, yellow, orange-yellow to brownish yellow, glabrous or reticulate; basal mycelium light yellow. Pleuro- and cheilocystidia subfusiform-ventricose or clavate, with subacute apex or long beak. Pileipellis an epithelium to an ixotrichodermium composed of distinctly inflated or cystidioid terminal cells. Basidiospores smooth, subfusiform, brownish yellow. Clamp connections absent. 2-3 species sister to Porphyrellus but lack deep node support with four genes (28S, tef1, rpb1, rpb2); Central China. Ectomycorrhizae presumed with Fagaceae.

Tuboseta Horak (=Setogyroporus fide Singer) (1967) (as Tubosaeta) Pileus dry, subvelutinous to tomentose, microscopically a trichodermium or subhymeniform. Context white. Hymenophore adnate to adnexed, olive yellow, sometimes staining greenish. Stipe dry, subvelutinous to glabrous. Spore deposit brownish yellow. Spores brownish yellow in deposit, smooth (light microscope) bacillate (SEM), fusoid. Hymenial cystidia present as thick-walled, pigmented setae. Clamp connections absent. Africa and Madagascar. Ectomycorrhizae with caesalpinoid legumes.

Turmalinea Orihara & N. Maek. (2015) Basidiomata sequestrate, hypogeous, subglobose to reniform, rubbery, pink to white of brownish white, often changing to blue when bruised. Gleba white, becoming blackish brown, loculate. Columella absent, but sterile base sometimes present. Peridium thin, composed of filamentous hyphae. Spores statismosporic, ovoid to fusoid, inamyloid, red to dark brown with 5–10 longitudinal ridges, often branched. Clamp connections absent. Four species known from Japan and China. Allied to Rossbeevera in the Leccinoideae using molecular inference. Ectomycorrhizae presumed with Fagaceae

Tylocinum Y.C. Li & Zhu L. Yang (2016) From the protologue: Basidiomata stipitate-pileate with tubular hymenophore. Pileus hemispherical or applanate; surface densely covered with granular or tomentose squamules, dry; context soft when mature, white to pallid, without discoloration when injured. Hymenophore depressed around apex of stipe; hymenophoral surface white to pallid or pinkish when young, and becoming pink to grayish pink when mature; pores relatively wide up to 1.5 mm, angular; tubes concolorous with hymenophoral surface, color unchanging when injured. Stipe central, concolorous with pileus or much deeper in color than the pileus; surface with concolorous verrucose or granular like squamules; basal mycelium pallid. Basidiospores subfusiform, smooth (under SEM). Pileipellis a trichodermium, composed of hyphae with 3–5 concatenated cells. Pleuro- and cheilocystidia fusiform to subfusiform, often with a sharp apex and a long pedicel. Clamp connections absent. Gene inference places genus in leccinoid clade sister to Retiboletus (Vadthanarat et al 2018). One species known from SW China. Ectomycorrhizae presumed with Fagaceae.

Tylopilus P. Karsten (1881) Pileus dry, glabrous to subtomentose, microscopically a trichodermium or subhymeniform. Context white, unchanging or staining pale brown, red then black, or rarely blue, with mild or bitter taste. Hymenophore adnexed, white then pinkish flesh colored to purplish brown to rusty brown, staining brown. Stipe dry, pruinose to glabrous to reticulate, to finely scabrous. Spores pinkish flesh colored to purplish brown, to rusty brown in deposit, smooth, fusoid to ovoid- phaseoliform. Hymenial cystidia present as pseudocystidia. Clamp connections absent. Some concepts include Porphyrellus; some (ballouioids) erroneously treated in Rubinoboletus (=Chalciporus), but molecular inference distinguishes Tylopilus from Porphyrellus, and embraces the ballouioids in Tylopilus. North Temperate, montane Neotropics, northern South America, southern and NE Brazil, E Asia, SE Asia, Australia, New Zealand, Africa. Ectomycorrhizae with Pinaceae, Fagaceae, Betulaceae, Nothofagaceae, Myrtaceae, Casuarinaceae, Caesalpinoid legumes.

Veloporphyrellus Gómez & Singer (1984) Pileus dry, tomentose, white to brown, microscopically a trichodermium. Context white, pale burgundy red. Hymenophore white to pinkish flesh color, unchanging. Veil present. Stipe white, annulate. Spores possibly purplish brown (?) in deposit, smooth, fusoid. Hymenial cystidia present. Clamp connections absent. Six species known from North America, Central America, E Asia, Africa. Ectomycorrhizae presumed with caesalpinoid legumes, Dipterocarpaceae, Fagaceae and Pinaceae.

Wakefieldia Corner & Hawker (1953) Basidiomata globose-depressed, minutely subtomentose, white then yellow, subcartilaginous, lacking a columella, with a sterile, golden yellow, sterile base. Gleba white then vinaceous pink, with gyrose lacunae, not becoming rubbery or gelatinous. Spores globose, sculpted with irregular curved plaques, sectors or wedges, thick-walled, cyanophilic. Type species: W. striaespora from Singapore. Molecular inference places the genus in the Zangioideae. Ectomycorrhizae not noted, but possibly presumed with Dipterocarpaceae and or Fagaceae in Thailand based on collections in NY gathered in 2006.

Xanthoconium Singer (1944) Pileus dry, subtomentose, often wrinkled, microscopically hymeniform. Context white, unchanging. Hymenophore adnate or adnexed, white to straw yellow, not staining. Stipe dry, glabrous. Spore deposit bright rusty brown. Spores smooth, fusoid to cylindrical. Hymenial cystidia present. Clamp connections absent. E North America south to southern Colombia, E Asia, Australia, possibly SE Asia. Ectomycorrhizae with Fagaceae, possibly Pinaceae in America. Myrtaceae, Casuarinaceae in Queensland, New South Wales.

Xerocomellus Šutara (2008) Pileus dry, matte, neither viscid nor sticky when moist, glabrous, velutinous or pruinose, usually without a distinct fibrillose aspect when young, becoming subtomentose with age, often cracking with age and then areolate-rimose. Pileipellis a palisadoderm. Hymenophore adnate or shallowly depressed or sometimes subdecurrent, yellow to olive brown, cyanescent or not, with angular pores. Tube trama intermediate (boletoid-phylloporoid). Stipe minutely granulose, sometimes longitudinally striate but mostly non-reticulate. Lateral stipe stratum usually absent or quite reduced. Spores smooth or longitudinally striate/veined, sometimes truncate. Hymenial cystidia present. Clamp connections absent. North Temperate, montane Neotropics, northern South America, East Asia, SE Asia, Australia, New Zealand, Africa. Ectomycorrhizae with Pinaceae, Fagaceae, Betulaceae, Nothofagaceae, Myrtaceae, Casuarinaceae, caesalpinoid legumes.

Xerocomus Quélet (1 8 8 7 ) Pileus dry, matte, subtomentose, microscopically a trichodermium. Pileipellis a trichoderm. Context white or yellow, sometimes cyanescent. Hymenophore adnate or shallowly depressed or sometimes subdecurrent, yellow to olive brown, cyanescent or not, with angular pores. Tube trama often 'phylloporoid,' not gelatinizing. Stipe central rarely eccentric, dry, glabrous to longitudinally ribbed but if reticulate then at apex, sometimes minutely floccose-granulose. Lateral stipe stratum thick, never gelatinous. Spore deposit olive brown. Spores subfusoid to fusoid-elliptical, smooth with light microscopy, 'bacillate' with SEM. Hymenial cystidia present. Clamp connections absent. North Temperate, montane Neotropics, northern South America, East Asia, Southeast Asia, Australia, New Zealand, Africa. Ectomycorrhizae with Pinaceae, Fagaceae, Betulaceae, Nothofagaceae, Myrtaceae, Casuarinaceae, caesalpinoid legumes.

Zangia Y.C. Li & Zhu L. Yang (2011) Pileus dry, pubescent and rugose, microscopically an ixohyphoepithelium. Context white, unchanging. Hymenophore adnexed, white then pinkish to pink or purplish when mature, unchanging. Stipe central, dry, whitish to yellowish or reddish, with red to purplish red scabrous squamules, chrome yellow at base, with context slowly cyanescent in some. Spores pinkish to pink to pale purple in deposit, smooth, subfusoid or ellipsoid. Hymenial cystidia present. Clamp connections absent. So far, known from Southern China. Ectomycorrhizae with Pinaceae, Fagaceae.